Speed-indicator.



A. L. R. ELLIS.

SPEED INDICATOR.

APPLICATION FILED MAYB,1906.

926,861, L Patented July 6, 1909;

2 SHEETS-SHEET 1.

Witnesses Inventor j 24j/.Z frlvarado LREIHS,

monzw. E MAMAN co.. Photo-ummm. wnmvon. D. c.

A! Ll Rl SPEED INDICATOR.l

APPLIOATION FILED IAY 8,1906.

Witnesses:

mouw. l. onmm co. Pu rcMmooMPMns. mamma n UNITE-D STATES PATENT OFFICE.

ALVARADO L. R. ELLIS, OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERALELECTRIC COMPANY, A CORPORATION OF NEW YORK.

SPEED-INDICATOR.

Specification of Letters Patent.

Patented July 6, 1909.

` and durable.

My invention relates more specifically to that type oli' speed indicatoror tachometer known as the liquid tachometer. In this type ol'instrument the speed is indicated by a column oi liquid, the height oiWhich is caused to vary as the speed which is to be measured.

The particular type .of liquid tachometer to Which I have applied myinvention comprises a revolving vane or paddle wheel which is rotated bythe part the speed. ol' 'which is to be indicated. This paddle Wheel isimmersed in a receptacle coi'itaining liquid, and provision is madewhereby the Wheel .forces the liquid into an indicator tube, the heightto which it will rise depending upon the speed of the Wheel. Devices oi'this character are Well-known and it is one oi' the objects oi myinvention to improve this type oi instrument so that it may be used lfora variety of speeds While having substantially the same lrange ofmovement in the iiiidicating tube.

Another object oi' my invention is to produce a liquid tachometerWl'iich will have no join ts below the level oi' the operatiu liquid, sothat there Will be no leakage.

My invention further consists in the i'eatures oi' construction and inthe arrangement and combination oi' elements heren after set forth andparticularly pointed out in the claims annexed to and forming a part oi'this application..

In the drawings, in which I have shown my invention embodied. in aspecific type oi mechanism, Figure 1 represents a iront elevation ol" mydevice, partly in section; Fig. 2 is a plan vieiv oi the same with thecover removed, certain parts being in section; Fig. 3 is a sideelevation oi' device shown partly in section; and Fig. 4 is a sectionalelevation of a modified form oi' my invention.

Referring to the drawings, l represents a liquid receptacle which may beoi any suitable iorm and material. lt is preferably, however, east incircular form, as shovvn, having a Wide flange 2 adapted forrecciving acover 3. The bottom ci the receptacle is cliainbered out so as to have asmaller di arneter, forming a shoulder 4 for supporting the bracket 5.This bracket forms a bearing for the shaft 6, preferably mounted in ballbearings 7 in the bottom of the receptacle. A paddle Wheel or puinpingelement 8 is lreyed to this shaft Within the chambered portion. oil thereceptacle and has a diameter slightly less than this portion of thereceptacle. The slraiit passes through the bracket 5 and is provided atits upper end With a bevel gear 9 extending above the receptacle. Thecover 3 is cut away so as to receive this gear and also the gears Whichdrive it. A shaft i0, provided With a driving pulley il, is mounted inthe cover 3, a bushing 12- Which may be ol anti-iirietion metal-beingprovided and secured in place by means of a set screw 13. The shalt 10extends Within the cover and at its inner end is provided With a bevelgear 111i keyed thereto and meshing With. gear A second shaft 15,preferably at right angles to the shaft 10, extends through the cover,the tivo shafts 15 and l() having an inner bearing in the cover, assbovvn at 16. Shaft l5 has also secured to it a bevel gear i7 meshingwith a bevel gear 1.8 secured. to the inner end ol" shaft il). From thearrangement oil." gearing it will be seen that the shalit 6 may bedriven by either of the shafts 10 or l5, tlic .ratio ol Athe gearingpreferably being such that when it is driven from shalt 15 it will berevolved much faster than when driven by shaft l0. An indicator tube1.9, Jrelerably of glass, is mounted in the receptacle l and secured inplace by means of a packing nut20. This tube extends down. to thechambered portion ol the receptacle adjacent to the paddle wheel S andcommunicates with the chamber by means of a passage 21. A properlygraduated4 scale 22 is arranged adjacent to the indicator tube and maybe graduated so as to read in revolutions per minute, if desired. Theupper' end of the tube is secured in place by means of a sup ort 23 andpacking nut 24. This support is iollow, so as to form a passage betweenthe in.- dicator tube and a second tube 25 which may be of any desiredn'iaterial and which is also secured to the support by means of the nut26. This tube, which may be of iron or brass, has its lower end threadedinto the receptacle at 27 and communicates with a passage 28, whichleads bach into the upper portion of the receptacle. rihe mode ofoperation of tnis forni of my device is very simple. hen either of theshafts l() or 15 is rotated the paddle wheel 8 is likewise rotated, foreing` the liquid which may be water or mercury-up into the indicator'tube, the height to which it rises depending upon the speed of rotation,so that if the scale be properlj,v graduated tire height will indie tethe revolutions of the shaft. ln case the speed becomes excessive andthe liquid rises vtoo high in the tube, it will flow through the passagein support 2Q and back through the tube 25 to the receptacle.

By the construction which l have shown the receptacle may be made of asingle casting and no joints will be below the level of the liquid. hecover will be secured to the receptacle by means of screws 29, a gasket30 being interposed to make a tight ljoint. Either shaft l() oridepending upon the speed to be measured-may be used. The shafts arearranged at right angles, so that when one shaft is being used anaccurate check will be given to the instrument by measuring the speed ofthe other shaft.

ln Fig. l l have shown a modified form of my invention, in which anotheror additional arrangement is provided for adapting the machine to avariety of speeds. The shaft 31 is provided with a plurality of paddlewheels constituting pumps, in this case three in number, 32, 33 and 3a.These wheels are preferably of a diameter such that the indications inthe tube 35 will be multi )lesl of each other. The receptacle in thisform is provided with chamber for each wheel and passages 36, 37 andSSS-one for each chamber--communicating with the indicator tube. In eachpassage is a valve 39 which may be operated to open or close thepassage, as desired. By this construction it will be seen that a longscale instrument is produced without the disadvantage of the long glasstube, which is liable to be broken. ln case the speed to be measured islow, passages 37 and 3S may be closed and the wheel 32 which is thelargest of the series will operate and pump the liquid, up the tube. Thediameter of the wheels is preferably such that the range in the glasstube may be kept substantially the same by using the proper paddlewheel. This arrangement may be used with the two drive shafts, ifdesired. It should be understood that by the term pump, as herein used,is meant any device whereby a head of liquid is produced.

lt will. thus be seen that l .have provided a tachometer which isexceedingly simple and cheap to construct. rlhe receptacle is simplyeast in one piece and all joints are above the level of the liquid. lhave furtl'rer provided an instrument which can be used for both highand low speeds without changing the length of the indicator tube.

Vilhile l have shown and described a specific construction andarrangement of parts, it should be understood that l do not limit myinvention except in so far as it is limited hy the scope of the claimsannexed hereto.

1iWhat f claim as new and desire to secure by Letters Patent of theUnited States, is:

l. fr speed indicator comprising a liquid receptacle, a pump and pumpshaft mounted taerein, a cover for said receptacle, and a pair of driveshafts mounted in said cover at an angle with each other and operativelyconnected with said pump shaft for driving the latter at differentspeeds.

a. A speed indicator comprising a liquid receptacle, a pump and a shaftvertically mounted therein, a cover for said receptacle, and a pair ofhorizontal drive shafts mounted in said coverat an angle with each otherand operatively connected with said pump shaft for driving the latter atdifferent speeds.

3. A speed indicator comprising a liquid receptacle, a pump and pumpshaft mounted therein, a pair of drive shafts at an angle with eachother and arranged to drive said pump shaft at different speed ratios.

4. A speed indicator comprising a liquid receptacle, a pump and a pumpshaft verticaly mounted therein, a pair of horizontal drive shafts at anangle with each other and arranged to drive said pump shaft at differentspeed ratios.

5. A speed indicator comprising a liquid receptacle, an indicator tube,a plurality of pumps mounted in said receptacle, and means for oneningor closing communication between said tube and any of said pumps atwill.

G. A speed indicator comprising a liquid receptacle, an indicator tube,a plurality of pumps mounted in said receptacle, and means for renderingany of said pumps effective in forcing liquid into said tube.

7. A speedv indicator comprising a liquid receptacle, an indicator tube,a drive shaft, a plurality of paddle wheels driven thereby, and meansfor rendering any of said wheels effective in forcing liquid into saidtube.

8. A speed indicator comprising a liquid receptacle, an indicator tubecommunicating t ierewith, a drive shaft, a plurality of pumps driventhereby each having a passage coinmunicating with. said tube, and meansfor opening or closing any of said passages at will.

9. A speed indicator comprising a liquid receptacle, an indicator tubecommunicating therewith, a drive shaft, a plurality of pumps ofdifferent capacities driven thereby each having a passage communieatinglwith said tube, and means for opening or closing any of said passages atwill.

10. A speed indicator comprising a liquid receptacle, an indicator tubecommunicating therewith, a vertical drive shaft, a plurality of paddlewheels .mounted on said shaft each having a passage communicating Withsaid tube, and means for opening or closing any of said passages atwill.

1l. A speed indicator comprising a liquid receptacle, an indicator tubecommunicating therewith, a cover for said receptacle having' a driveshaft mounted therein, a vertical shaft driven by said drive shaft, aplurality of paddle wheels mounted on said vertical shaft each havingn apassage communicating with said tube, and means for opening or closing'any of said passages at will.

12. A speed indicator comprising' a liquid receptacle and a covertherefor, a shaft vertically mounted in said receptacle, a pair of driveshafts mounted in said cover and arranged to drive said vertical shaftat different speeds, an indicator tube, a plurality of paddle Wheelsmounted on said vertical shaft each havingI a passage communicating`With said tube, and means for opening or closing any of said passages atWill.

l'n Witness whereof, l have hereunto set my hand this fifth day of May,1906.

ALVARADO L. R. ELLIS.

lNitnesses 1 JonN A. MoMANUs, Jn., HENRY O. WEsTENDARP.

